If the circles $x^2 + y^2 + 2ax + cy + a = 0$ and $x^2 + y^2-3ax + dy - 1 = 0$ intersect in two distinct points $P$ and $Q$, then the line $5x+by-a = 0$ passes through $P$ and $Q$ for :

Question

( A ) infinitely many value of a
( B ) no value of a
( C ) exactly one value of a
( D ) exactly two values of a